Methods of pbeparation there-



Patented Jan. 5, 1954 I UNITED STATES PATENT OFFICE SPIROCYCLOHEXYLQUINOLINES AND MFI ITHODS F PREPARATION THERE- 0 Louis H. Schwartzman, Pittsburgh, Pa., and Gilbert Forrest Wofods, Jr., Silver Spring, Md. No Drawing. Application July 9, 1952,

a Serial No. 298,194

6 Claims. (Cl. 260-283) This invention relates to compounds-oi the producing therefrom a large number of new, spirocyclohexane type and methods-of preparanovel and useful analgesic compounds containtion thereof. ing a quaternary carbon atom in the molecule More particularly, the invention relates to the and, in addition, either a primary, secondary, or synthesis of compounds of the spirocyclohexane tertiary amine group. type, particularly those having analgesic proper- The invention also provides new and novel ties Su h as possessed by morphine andoth r methods of preparing the compounds described opiates derived from natural sources. herein, such methods being particularly advan- Considerable elfort has been directed in the tageous in view of the simplicity of the procepast toward the synthesis of suitable analgesics 10 dures, economic practicability and comparatively as substitutes for morphine and the like, parhigh yields of the intermediates and the end prodticularly in view of the fact that the principal ucts without the use of complicated or expensive source of supply of morphine and related comstarting materials, apparatus, or processes. pounds is dependent upon natural sources, most The intermediates required for synthesis of the of which are presently located in the Orient. In 5 compounds of the present invention may be prean effort to produce chemically synthesizedanal- I pared, for example, in the manner described in gesics domestically on an economically practicopending application Serial No. 150,806, now cable basis, and to provide a source of analgesics Patent No. 2,586,486, by using cyclohexanone as independent of natural supplies of raw materials, a starting material, treating it with a mixture many attempts have been made to synthesize of calcium carbide and potassium hydroxide to various analgesics as substitutes for morphine yield an acetylenic glycol such as 1,1'-ethynyleneand the like, some of the more recently developed bis-cyclohexanol according to the reaction:

compounds being 0 OH on v C50 000m +CaCl+KOH This glycol (II) is then dehydrated to the dieneyne (m) by, for instance, heating the above glycol under reflux conditions with dilute sulfuric acid as follows: Demerol 0H 0H 85 050T Toast C-O-C2Ha (n) (In) H, The compound thus obtained is then cyclized -and hydrated, for example, by refluxing with (EH-M0391 formic acid, thus producing as intermediates, H, cyclic ketones such as 'spiro [cyclohexane-1,1- Methadon A9-tetrahydroindanone3'l (IV) and its isomer etc. spiro [cyclohexane- 1,1-A8'-tetrahydroindan even in some cases are unsuitable for use by 050 human beings becaues of their high toxicity or side-effects and other undesirable properties.

It is found that compounds of the present invention are not relatively simple and inexpensive to manufacture from readily available raw materials but, in addition, have satisfactory anal- Am n other things, 1t has been found that one-3'] (V) in accordance with the following gesic properties and are of sufficiently low toxicity to permit safe use by human beings.

many synthetic compounds produced heretofore, reaction; 7 although having some of the analgesic properties of morphine and the like, are not satisfactory from the standpoint of manufacturing costs, and 5 (III) i v and/or In its more specific aspects the presentinvention pertains to the synthesis of analgesic comg positions ofthe spirocyclohexane type by employing cyclohexanone as a starting material and (v) To producethe. analgesic compoundsziofi' the; present invention, the cyclic ketones (IV) and/or (V) are converted to the aromatic ketone (VI)- according to the following reaction as set forth in copending patent application serial" No;- 150,806, now Patent No. 2,58%;486 issuecf-Febrwary 19, 1952:

\ Catalyst and/or TherketoneXVI) is converted to spirot'cyclm hexane-l,4-dihydrocarbostyril] (VII) by appropriate treatment with hydrazoic acid'or' so- Reduction v i '4, a dilum azideintheipresenceol sulfizriciacid. According to the reaction:

t (VI) (VII) Essentially this is the same result that can be I achieved by'a-Beckmann rearrangement of the oxime: of spiro [cyclohexane- 1,1 -indanone-3 1' Beckmann-..

-v Rcum-rmgeme'nt' This-material (VH7 is. then utilized in'a' series.

of chemical transformations as" shown below to yield spirocyclohexylhydroquin-olines of thepresant-invention which. have substituents' either on the: heterocyclic nitrogen. atom or' substituents in the aromatic nucleus, or substituents in: both positions where R is' Hydrogen, lower alkyl or acyl EI'OUPS' q (i W 7 (VIII) Nitrstion Reduction --0 O|N H:N- 1 1 Diazotization and Omlhylstion --v -,-r Replacemeht:

It is an object of the present invention, therefore, to provide a series of spirocyclohexylhydroquinolines having analgesic properties. It is a further object of the present invention to provide a series of spirocyclohexylhydroquinolines having in the molecule a quaternary carbon atom and, in addition, a secondary or tertiary amine group. It is a still further object of the invention to provide substituted spirocyclohexylhydroquinolines. It is a still further object of the present invention to provide methods of preparation of the compounds of the invention.

For purposes of illustration, but without limiting the scope of the patent thereto, representative methods and compounds of-the present invention are described in the following examples:

Example I and stirred continuously for thirty minutes after the evolution of nitrogen had ceased, was cooled and the benzene layer decanted from the sulfuric acid layer. Ice was added, with efiicient cooling and mechanical stirring, to the sulfuric acid layer. Continual stirring for one hour and the addition of small portions of ether caused the oily layer to crystallize. Yellow solid 'spiro[cyclohexane-L4'-dihydrocarbostyrill (VII) (10.5 g., 71%) so formed is pure enough for use in subsequent reactions. Recrystallization from alcohol-water mixture produced a white, analytical sample melting at 185-1855". This compound has the formula:

Example I! To a cooled solution of 100 ml. of a 1.2 molar (100 per cent excess) of lithium aluminum hydride in ether, 26.6 g. of spiro[cyclohexane-1,4'- dihydrocarbostyril] in 200 ml. of dry benzene Was added drop-wise over one hour; the reaction Then the benzene layer was decanted, and the gelatinous residue extracted with ether. The amine, spiroEcyclohexane 1,4 1',2,3',4' tetrahydroquinolinel (VIII), was isolated by acid-base extraction and B. P. 156157 (1.5 'mm.), 23.7 g., or 96%. It crystallized from petroleum-ether (30-60") in a Dry Ice bath and sublimed readily under reduced This compound possesses the analgesic effects on w ite mice described in the following chart:

M. E. D.: 150 mg./kg. body weight. L. D. 50: 300 mg/kg. body weight.

Example III A suspension of 2.7 g. of the amine spiro [cycloexane 1,4 1,2,3,4 tetrahydroquinoline] (VIII) in 10 ml. of'water was refluxed for four hours with 1.73 g. of dimethyl sulfate, and then allowed to stand at room temperature for fortyeight hours. Ammonium hydroxid was added and the basic solution extracted with ether. The amine (2.5 g.) was isolated in the usual manner. This oil was reacted with benzoyl chloride and dilute sodium hydroxide and the unreacted oil extracted with ether. Spirolcyclohexane 1,4- N-methyl-l',2,3',4'-tetrahydroquinolinel (1.25

43%) isolated in the usual manner was distilled under nitrogen: B. P. 134135 (1 mm.), 7t 30=1.5778. This compound has the formula:

,on w te mice described in the following chart:

M. E. D.: mgr/kg. body weight. D. 50: 750 mg/kg. body Weight.

Example IV 'spirolcyclohexane 1,4 1,2,3',4' tetrahydroquinolinel (VIII) is dissolved in about 4 :molar equivalents of acetic anhydride and to this vent is removed under reduced pressure and the residue, spiroEcyclohexane 1,4 N acetyl- 1,2,3',4' tetrahydroquinolinel is recrystallized from water and subsequently sublimed to yield a. white, crystalline material melting at 100102 C. This compound has the formula:

=0 (5H3 I EmmpleV Spirowyclohexane 1,4'-Nmethyl 1',2',3',4'- tetrahydroquinolinel hydrochloride (3.5- g.) is

- dissolveiin concentrated sulfuric :acid 1011111.) cooled andmarbon. tetrachloride (100ml) added. The two phase system is cooled to 4 C. to -5 C. and with efficient mechanical stirring, potassium nitrate (1.42 g.) in concentrated sulfuric acid (5 ml.) is added over a period of fifteen minutes. The red, mixture is then allowed to stir for one and one-halfxhours and then the carbon tetrachloride layer decanted away and the sulfuric acid layenpoured with stirring onto cracked ice. The mixture is then neutralized with sodium bicarbonate and the resulting alkaline mixture extracted with ether. Concentration of the dried ether extract under .reduced pressure affords spiro methyl x nitro- 1",2,3',4 tetrahydroquinoline] which is theneonverted to the hydrochloride by the addition of absolute alcohol saturated with. hydrogenchloride gas. 'Ihe..hydrochloride melts. at246 252" LC. (decomposition) .nitroaminehas the formula Example VI -Spir0lcyclohexane -'1,4 N methyl-x-nitro- 1,2,3,4 tetrahydroquinolinel hydrochloride (0.25 g.) was dissolved in '75 ml. of alcohol and hydrogenated at 1 atmosphere of hydrogen at 25 C. with 0.1 g. of Adams catalyst. The absorption of hydrogenstopped after fifteen minutes and the catalyst was filtered away and the filtrate concentrated to dryness under reduced pressure. The resulting monohydrochloride of spiroEcyclohexane 1,4 x amino N methyl- 1,2,3,4 tetrahydroquinoline] was a hygroescopic sblid. Therefore 1 the "free .1 amine was liberated with base andextracted with ether and dried. Upon concentration of the dried ether solution, the oily diamine resulted. .lnorder'to accurately establish the structure, the diamine was treated with acetyl chloride and the result- .ing white solid after recrystallization from. alcohol-ether:mixtures melted atj255-260' (decomposition) Analysis showedthe structure tolfne'z Example .VIII ..Splro[cyclohexaneeLA x .-.nitro 1325.3 .41

.tetrahydrcquinolinelhydrochloride is dissolvedin 16 [cyclohexane 1,4 N-.

' 'The .free .7

5011111. :of-zahsolutezaleoholrand.theated to "reflux withstanding. LiIhen 511612'21120 121 g.) .inea z'mixture :of concentrated hydrochloric :acid .(20 ml.) and-alcohol .(25 m1;) -.is; added 'dropwiseover 6 ;a period of fifteen-minutes. :The mixture is .stirredand refluxedjor an -.additional one and .'.oneehal'hours. Thejalcohol :isthen removedunder'reducedgpressuregandthe; acid solutionmade definitely alkaline with :concentrated pota's- 10 mm; hydroxide. .The'ramine .is extracted with ether, ;..dried:.and concentrated v.to zxgive about .3 grams DfIbIiOWIlLOiI. Itissublimedatabouttlfio" 0.: at .11: mm. and ,the: resulting oil is crystallized and clarified. iromi60-80- petroleum ether .toyield 15 white crystalline spirolcyclohexane -.1,4' --x amino -.1.';,2.*,,3' ;4"'- tetrahydroquinoline] which melts at 9597 C. This compound has the formula:

.Emam'pZeJX spiromyclohexane 1A x amino 1",2

3,4=tetrahydroquinoline] (2 g.) was .dissolved in 2.ml. of acetic anhydride and 1.5.ml. of pyri- .dine. This mixture was allowed .to stand .iour days atroom temperatureand thenthe solvent was removed under-reduced pressure on a. steam cone. .When .the resulting .oil .was triturated with cold-acetone a mass .of..white;.crystals wa obtained. 'Spir'olcyclhhexane-IA ;N acetyl x acetylamino -1 ',2.731;4' tetr'ahydmquinv.olinel so obtained .was frecrystallized .from .ace-

tone and melted at"'I'85.'5-l86.5' C.

I OH:

The crystalline diamide (prepared above) (1.4 g.) was added portionwise to a stirred solution of 10 ml. of 1.3 molar lithium aluminum hydride in ether. A vigorous reaction ensued; *after'the initial reaction subsided, the mixture was-stirred and refluxed for an additional 24 hours. The mixture was chilled with an ice bath and decomposed'with ice water. The ether layer was'separated, dried, and concentrated to give- 019 g. of oily spiro [cyclohexane-IA' -N-ethyl- -x 'ethylamino 1',2" ,3 ;4' tetrahydroquineline]. 1

9 4. Example X Spiro[cyclohexane 1,4 x amino N methyl-1',2',3',4'-tetrahydroquinoline] is dissolved in dilute sulfuric acid and the solution is stirred and cooled to to 5 C. by means of an ice-salt bath. To this solution is added dropwise an aqueous solution of sodium nitrite. The temperature of the reaction mixture is main-- tained at 0 to 5 C. during this period by the addition of ice, if necessary. When a slight excess of the sodium nitrite solution has been added stirring is continued for an additionalfifteen minutes and then a small amount of urea dissolved in water is added to destroy the excessnitrous acid.

The resulting solution is made more acidic by the addition of 60% sulfuric acid until the concentration of the sulfuric acid is 2 to This solution is now heated on a steam bath or by means of direct steam introduction into the solution until the reaction temperature is about 95 to 105 and this temperature is maintained for an additional hour, at which time the nitrogen evolution has ceased.

The solution is cooled and made slightly basic with ammonium hydroxide. Extraction with ether and subsequent removal of the ether under reduced pressure affords a residue which is spiro[cyclohexane 1,4 x hydroxy N methyl-1 ',2 ,3 34' -tetrahydroquinoline] having the formula:

Example XI Spiro[cyclohexane 1,4 x hydroxy N- methyl-1,2,3',4'-tetrahydroquinoline] is dissolved in aqueous potassium hydroxide and the solution is refluxed. To this refluxing solution an equivalent amount of dimethyl sulfate is added dropwise and the mixture is then refluxed for an additional few hours. The alkaline mixture is cooled and extracted with ether; concentration of the dried ether extract under reduced pressure afiords spiroEcyclohexane 1,4 x methoxy- N methyl 1',2',3',4' tetrahydroquinoline]. This compound has the formula:

(I) Hz Example XII Spirolcyclohexane 1,4 x hydroxy N- methyl 1',2',3',4 tetrahydroquinoline] is dissolved in 4 molar equivalents of acetic anhydride and then a catalytic amount of pyridine is added. After several days at room temperature, the solvent is removed under reduced pressure to yield as a residue spiro[cyclohexane-1,4-x-acetoxy-N- 1 0 methyl 1'.2',3',4=' tetrahydroqulnolinel having the formula:

12.5 g. of spiro[cyclohexane-1,l-x'-methoxyindanone-B] in 125 ml. of benzene and 22 m1. of sulfuric acid was heated to 55 C. and 4.9 g. of sodium oxide was added over one-half hour. The sulfuric acid layer was separated and decomposed with ice to yield 5 g. of spirolcyclohexane- 1,4-x-methoxydihydrocarbostyril] which after recrystallization from dilute methanol melted at Example XIV In the same manner as Example II. spirolcyclohexane-1,4-x-methoxydihyroearbostyrill was re-.

duced quantitatively with lithium aluminum hydride to yield spiro[cyclohexane-L4-x-methoxy- 1',2,3',4'-tetrahydroquinoline] which after recrystallization from petroleum ether and subsequent sublimation melted at 7 6-77 C.

This compound is readily demethylated in the usual manner to spiro[cyclohexane-1,4'-x-hydroxy- 1 ,2 ,3 ,4 -tetrahydroquinoline] In the foregoing examples it will be understood that in lieu of the methyl group other lower alkyl groups such as ethyl, propyl, etc., may be incorporated in the molecule by proper selection of the reacting materials in the manner obvious to those skilled in the art. Likewise, it will be understood that the alkoxy group may be methoxy, ethoxy, propoxy, etc., the acyl group may be acetyl, propionyl, butyryl, etc., and the halogen may be the chloride, bromide iodide, fluoride, etc.

The term M. E. D. is used herein as an abbreviation for the minimal effective dosage for 50% of the animals tested. The term L. D. 50 is used herein as an abbreviation for the lethal dosage for 50 of the animals tested.

This application is a continuation-in-part of copending application Serial No. 150,810, filed March 20, 1950.

It will be understood that other modifications may be made in the foregoing examples without 1t 12 departing fromtfie -seopvofithe' inventlbni Item 4. Spirocyclohexylhydtoqumolines of the forintended, therefore, that the patent shall -coven mule: I by suitable expression in the appended claims 1 the features of patentable novelty residing in the invention. 5

We claim:

1. Spirocyclohexylhydroquinolines of the type:

5;. Spirocyclohexylhydroquinolines of the for-- mule:

wherein R is. selected'from. the group; consisting. of hydrogen, lower alkyl groups and. lower. acyl groups andXis selected fromwthegroup, consist-- ing of. hydrogen, hydr.oxyl,'.alkoxyl groups, lO-acyl groups, nitro and amino groups.

2. Spiro [cyclohexane-lA -N-methyl-1",2 ,3 ,4

tetrahydroquinolinel' of the formula: CH1

6:: Spirocyclohexylhydroquinolines. of the formula:

CH5 3. Spiroeyclohexylhydroquinolines of the forl mula': 0H;

LOUIS H. SCHWARTZMAN. GILBERT FORREST WOODS, JR.

No references cited. 

1. SPIROCYCLOHEXYLHYDROQUINOLINES OF THE TYPE: 